The potential for complementary targeted/non-targeted screening of novel psychoactive substances in equine urine using liquid chromatography-high resolution accurate mass spectrometry

Abstract

The potential for liquid chromatography-high resolution accurate mass (LC-HRAM) spectrometry to identify 'unknown' compounds using non-targeted screening methods provides a potential advantage in the fight against doping in sport. This innovation comes with the requirement for assessment to support its use in the medico-legal context. A method for the LC-HRAM detection of 2,5-dimethoxy-N-(2-methoxybenzyl)phenethylamine (NBOMe) compounds in equine urine was validated in order to assess the capabilities of a workflow developed for non-targeted analysis using the SIEVE® differential analysis software platform. Six NBOMe compounds (25B, 25C, 25D, 25E, 25H and 25I) were studied to develop and optimize the proposed non-targeted screening workflow before two additional candidates (25N and 25T2) were used as blind controls for verification. Chromatographic alignment and the integration threshold were found to be the most critical parameters for successful identification of 'unknown' responses. The proposed workflow serves as an example for anti-doping laboratories to implement fit-for-purpose non-targeted screening methods.